GROWTH OF ALBUGO-CANDIDA (RACE UNIDENTIFIED) ON BRASSICA-JUNCEA CALLUS-CULTURES

An obligate fungus Albugo candida (Pers. ex Lev.) Ktze. (race unidenti fied) was successfully grown on host callus tissues of Brassica juncea cv. Varuna. Of the various type of diseased explants used, young (gre en) hypertrophied inflorescence axis bearing non-erumpent zoosporangia l blisters allowed the fungus to multiply asexually over the host call i on modified MS-medium (Murashige and Skoog, 1962). The dual cultures were maintained up to 6-8 subcultures without loss of viability of zo osporangia on MS-medium supplemented with 10.0 mg L(-1) IBA, 0.05 mg L (-1) kinetin, 25.0 mg L(-1) AA, 1.0 mg L(-1) biotin, 1.0 mg L(-1) thia mine-HCl and 1.0 g L(-1) casein hydrolysate. The fungus grew only on t he callus cells and not axenically on the medium. Pathogenicity test a nd histopathology of cultures proved the existence of the viable fungu s in vitro.